The dynamic behavior of the coherent flow between shrouded co‐rotating disks

Abstract

Time‐resolved measurements were made to study large‐scale structures between shrouded co‐rotating disks in the present work. Two laser velocimeters and a phase‐averaged technique were employed to investigate the dynamic behavior of the coherent structures. From the reconstructed streamline patterns, three distinct flow regions can be identified quantitatively: namely, an inner region nears the hub, an outer region, and a shroud boundary‐layer region. The outer region is distinguished by the presence of large vortical structures and it is the most energetic region in the flow field. Using a triple decomposition method, the Reynolds stress distributions associated with random fluctuation and coherent motion can also be deduced. It is found that both periodic and random Reynolds stresses contribute significantly to the total Reynolds stresses. The peaks of Reynolds stress distributions occur where the centers and saddles are passing.

Key words:

• laser doppler velocimeters
• phase‐averaged technique
• co‐rotating disks

Notes

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